System for rapid biohydrogen phenotypic screening of microorganisms using a chemochromic sensor

Abstract

Provided is a system for identifying a hydrogen gas producing organism. The system includes a sensor film having a first layer comprising a transition metal oxide or oxysalt and a second layer comprising a hydrogen-dissociative catalyst metal, the first and second layers having an inner and an outer surface wherein the inner surface of the second layer is deposited on the outer surface of the first layer, and a substrate adjacent to the outer surface of the second layer, the organism isolated on the substrate.

We claim:  
     
       1. A system for identifying a hydrogen gas producing microorganism, comprising: 
       (a) a chemochromic sensor film having a first layer comprising a transition metal oxide or oxysalt and a second layer comprising a hydrogen-dissociative catalyst metal, the first layer being deposited on a glass substrate on which said microorganism is isolated and the second layer is deposited on the first layer.  
     
     
       2. The system of  claim 1 , wherein the transition metal oxide is selected from the group consisting of WO 3 , Nb 2 O 3 , and CoMoO 4 . 
     
     
       3. The system of  claim 1 , wherein the hydrogen-dissociative catalyst metal is selected from the group consisting of platinum, rhodium, and palladium. 
     
     
       4. The system of  claim 1 , wherein the sensor film further comprises a fluorinated hydrocarbon polymer applied to the second layer of hydrogen-dissociative catalyst metal. 
     
     
       5. The system of  claim 1 , further comprising a means for separating the substrate and microorganism from the second layer. 
     
     
       6. The system of  claim 1 , further comprising a means for associating the location of the microorganism on the substrate in relation to the change in color on the film. 
     
     
       7. The system of  claim 4 , wherein the fluorinated hydrocarbon polymer comprises polytetrafluoroethylene. 
     
     
       8. The system of  claim 5 , wherein the separating means comprises filter paper. 
     
     
       9. The system of  claim 6 , wherein the associating means comprises a grid system consisting of a matrix of cells positioned in a spaced relationship to the substrate, a single colony of the microorganism circumscribed in relation to a boundary of the cell.